Trisomy 18 — What’s That?

Over the weekend, republican presidential candidate Rick Santorum reportedly took some time off to be with his three-year-old daughter Bella (short for Isabella), who was admitted to the hospital with pneumonia. Monday, Bella — who's known to have the genetic condition Trisomy 18 — was released from the hospital. And yesterday, Santorum announced he was suspending the campaign. So maybe Bella's health and the decision to withdraw aren't connected. But people are still wondering: What the heck is Trisomy 18 anyhow?

Well, according to the National Institutes of Health, Trisomy 18 (aka Edwards syndrome) happens when a baby gets extra genetic material from chromosome 18 — that causes developmental problems. The Trisomy 18 Foundation says this happens in about 1 out of every 3000 live births.

Babies with the condition often have clenched hands, crossed legs, curved feet, low birth weight, mental deficiency, a small head and other developmental issues.

In children with Trisomy 18, medical complications like Bella's pneumonia are more likely to be life-threatening. In fact, it's rare that children with the disorder make it to their third birthday the way Bella has. Sadly, 50 percent of Trisomy 18 babies who are carried to term are stillborn and less than 10 percent survive to age one. But there's a small number who live into their 20s and 30s — these adults have significant developmental problems and often need assisted living arrangements.

Unfortunately, Trisomy 18 can't be prevented, but you can find out your baby's risk. If you're pregnant or trying to get pregnant and you're concerned about Trisomy 18 or other genetic disorders, ask your doctor about genetic counseling. A counselor can help you and your partner compile your family health histories to weigh your baby's risk of certain genetic conditions and help you decide what type of genetic testing you may want to get while you're expecting.